Add local file:// source support for orchestrator image preparation

This commit enhances image handling in the orchestrator by adding support for `file://` sources. It introduces logic to handle both local file copying and decompression options, complementing the existing `http(s)://` download functionality.

crates/orchestrator/src/config.rs

@@ -100,8 +100,9 @@ fn default_example_path() -> PathBuf {
     PathBuf::from("examples/orchestrator-image-map.yaml")
 }
 
-/// Ensure images referenced in config exist at local_path. If missing, download
+/// Ensure images referenced in config exist at local_path. If missing, fetch
-/// from `source` and optionally decompress according to `decompress`.
+/// from `source` (supports http(s):// and file://) and optionally decompress
+/// according to `decompress`.
 pub async fn ensure_images(cfg: &OrchestratorConfig) -> Result<()> {
     for (label, image) in cfg.images.iter() {
         if image.local_path.exists() {
@@ -111,8 +112,39 @@ pub async fn ensure_images(cfg: &OrchestratorConfig) -> Result<()> {
         if let Some(parent) = image.local_path.parent() {
             tokio::fs::create_dir_all(parent).await.into_diagnostic()?;
         }
-        // Download to temporary file
+
+        let source = image.source.as_str();
+        let is_file = source.starts_with("file://");
         let tmp_path = image.local_path.with_extension("part");
+
+        if is_file {
+            // Local file source: copy or decompress from local path
+            let src_path = PathBuf::from(&source[7..]); // naive parse; paths should be absolute
+            tracing::info!(label = %label, src = ?src_path, local = ?image.local_path, "preparing base image from file:// source");
+
+            match image.decompress.unwrap_or(Decompress::None) {
+                Decompress::None => {
+                    // Copy to temporary then atomically move into place
+                    tokio::fs::copy(&src_path, &tmp_path).await.into_diagnostic()?;
+                    tokio::fs::rename(&tmp_path, &image.local_path).await.into_diagnostic()?;
+                }
+                Decompress::Zstd => {
+                    let src = src_path.clone();
+                    let tmp_out = tmp_path.clone();
+                    task::spawn_blocking(move || -> miette::Result<()> {
+                        let infile = fs::File::open(&src).into_diagnostic()?;
+                        let mut decoder = zstd::stream::read::Decoder::new(infile).into_diagnostic()?;
+                        let mut outfile = fs::File::create(&tmp_out).into_diagnostic()?;
+                        std::io::copy(&mut decoder, &mut outfile).into_diagnostic()?;
+                        Ok(())
+                    })
+                    .await
+                    .into_diagnostic()??;
+                    tokio::fs::rename(&tmp_path, &image.local_path).await.into_diagnostic()?;
+                }
+            }
+        } else {
+            // Remote URL (HTTP/HTTPS): download to temporary file first
             tracing::info!(label = %label, url = %image.source, local = ?image.local_path, "downloading base image");
             let resp = reqwest::get(&image.source).await.into_diagnostic()?;
             let status = resp.status();
@@ -124,16 +156,12 @@ pub async fn ensure_images(cfg: &OrchestratorConfig) -> Result<()> {
                 );
             }
             let bytes = resp.bytes().await.into_diagnostic()?;
-        tokio::fs::write(&tmp_path, &bytes)
+            tokio::fs::write(&tmp_path, &bytes).await.into_diagnostic()?;
-            .await
-            .into_diagnostic()?;
 
             // Decompress or move into place
             match image.decompress.unwrap_or(Decompress::None) {
                 Decompress::None => {
-                tokio::fs::rename(&tmp_path, &image.local_path)
+                    tokio::fs::rename(&tmp_path, &image.local_path).await.into_diagnostic()?;
-                    .await
-                    .into_diagnostic()?;
                 }
                 Decompress::Zstd => {
                     let src = tmp_path.clone();
@@ -151,6 +179,8 @@ pub async fn ensure_images(cfg: &OrchestratorConfig) -> Result<()> {
                     .into_diagnostic()??;
                 }
             }
+        }
+
         tracing::info!(label = %label, local = ?image.local_path, "image ready");
     }
     Ok(())

examples/orchestrator-image-map.yaml

@@ -32,6 +32,7 @@ images:
   openindiana-hipster:
     # All images are backend-agnostic and must support NoCloud. Backends are chosen by host.
     source: https://dlc.openindiana.org/isos/hipster/20250402/OI-hipster-cloudimage.img.zstd
+    #source: file:///home/toasty/ws/illumos/installer/cloudimage-ttya-openindiana-hipster.raw.zst
     # Local path (raw .img) target after download/decompression. Adjust per host.
     local_path: /var/lib/solstice/images/openindiana-hipster.img
     decompress: zstd  # if omitted, assumed already uncompressed raw or qcow2